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EP 2 359 932 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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03.04.2013 Bulletin 2013/14 |
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Date of filing: 23.12.2010 |
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International Patent Classification (IPC):
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Positive displacement pump with pressure sensor
Verdrängerpumpe mit Drucksensor
Pompe de déplacement positif doté d'un capteur de la pression
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Designated Contracting States: |
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AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL
NO PL PT RO RS SE SI SK SM TR |
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Priority: |
22.01.2010 US 692089
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Date of publication of application: |
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24.08.2011 Bulletin 2011/34 |
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Proprietor: Tecan Trading AG |
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8708 Männedorf (CH) |
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Inventor: |
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- Dzuong, Jimmy
Milpitas, CA 95035 (US)
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(74) |
Representative: OK pat AG |
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Chamerstrasse 50 6300 Zug 6300 Zug (CH) |
(56) |
References cited: :
EP-A1- 0 571 100 US-A- 5 499 545 US-A1- 2007 102 445
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EP-A1- 1 882 951 US-A1- 2004 159 675
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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Field of technology
[0001] The present invention relates to a positive displacement pump comprising a pump cylinder
and a pump piston. The pump cylinder comprises a longitudinal axis, a cylinder wall
extending parallel to the longitudinal axis, a cylinder bottom extending essentially
perpendicular to the longitudinal axis, and a cylinder outlet that is located in or
close to the cylinder bottom. The pump piston comprises a piston front that is reciprocally
movable inside the pump cylinder in direction of the longitudinal axis. The positive
displacement pump also comprises a cylinder space that is located inside the pump
cylinder and that is defined by the cylinder wall, the cylinder bottom, and the piston
front and a pressure sensor that is located in or outside of an orifice in the cylinder
wall for detecting the pressure in the cylinder space. The positive displacement pump
further comprises a pressure channel, a main portion thereof extending parallel to
the longitudinal axis of the pump cylinder, for providing fluidic connection between
the cylinder space and the pressure sensor. Such positive displacement pumps are preferably
used for aspiration into and/or dispensation of liquids from a pipette or dispenser
tip that is in fluidic working connection with the cylinder outlet of the positive
displacement pump. Positive displacement pumps e.g. comprise piston pumps, plunger
pumps and syringe pumps. Single and multiple arrangements of such positive displacement
pumps and their associated pipette or dispenser tips are contemplated for implementation
into a liquid handling device or liquid handling robot. Such liquid handling tools
are known from e.g. automated pipetters or dispensers that are accomplished to take
up and/or deposit liquid samples and that are a preferred part of liquid handling
workstations or robotic sample processors such as the GENESIS Freedom
® workstation or the Freedom EVO
® platform (both of Tecan Trading AG, 8708 Männedorf, Switzerland).
Related prior art
[0002] From the
US patent No. 5,499,545, a pipetting device is known which's measurement accuracy is improved by eliminating
the influence of changes in the atmospheric and internal pressures on the quantity
of a liquid absorbed or discharged. The pipetting device is equipped with a pressure
sensor that measures the pressure inside a cylinder portion of a piston pump. The
pressure sensor is fluidly connected to the cylinder portion by a piper portion that
is located between the cylinder and the pipette tip. A similar arrangement is known
from the European patent application
EP 0 215 534 A2, where a pressure gouge is fluidly connected to the tubing between the pump cylinder
and the pipette tube using a T-piece.
[0003] From the European patent application
EP 0 571 100 A1, a pipette apparatus which operates on the air-piston principle is known. Operation
is monitored and/or controlled on the basis of the air pressure measured by a pressure
sensor that is connected to the air space of the pipette. The pressure sensor is connected
to a cylindrical tube of the pipette so that it measures the air pressure in the cylinder.
A control unit registers pressure changes in the air space of the pipette and functions
as an alarm unit in case of a malfunction or controls the operation of the pipette
on the basis of the pressure changes in the air space of the pipette.
[0004] A dispenser and dispensing device is known from the
US patent No. 7,314,598 B2. The dispenser has a pressure sensor enabled to detect a pressure precisely by forming
a pressure sensor integrally with a syringe construction a nozzle to thereby eliminate
a pipeline or the like (as e.g. used in all earlier addressed prior art documents).
The dispenser is provided for sucking and discharging a liquid from a nozzle by slidably
moving a piston sliding inside of a syringe by a motor mounted in a body. A detection
sensor for detecting the internal pressure of the inside of the syringe is integrally
formed by connecting its air inlet directly to a through hole formed to extend to
the inner surface of the syringe. However, there is some dead-volume left at the cylinder
outlet, the pressure of which dead-volume cannot be measured by the proposed setup.
Objects and summary of the present invention
[0005] One object of the present invention is the provision of an alternative positive displacement
pump arrangement with a pressure sensor for use in a pipetting or dispensing devices;
the alternative positive displacement pump arrangement at least partially eliminating
drawbacks known from the prior art.
[0006] A first object is achieved with an improved positive displacement pump as introduced
at the beginning of the specification, the positive displacement pump comprising a
pressure channel, a main portion thereof extending parallel to the longitudinal axis
of the pump cylinder, for providing fluidic connection between the cylinder space
and the pressure sensor. The improvement according to the present invention is based
on the features that the cylinder wall comprises a piston sleeve, the piston sleeve
being located on the inner side of the cylinder wall and extending over essentially
the entire length of the pump cylinder to the cylinder bottom, and that the main portion
of the pressure channel is located in the cylinder wall comprising the piston sleeve,
the piston sleeve thus preventing the pump piston from touching or compromising the
pressure sensor or an inner surface of the cylinder wall when moving past the position
of the pressure sensor. Additional aspects and inventive elements derive from the
dependent claims.
[0007] The positive displacement pump arrangement according to the present invention at
least provides for the following advantages:
- The dead-volume of the pump, i.e. the volume in which the pressure differs according
to the movement of the pump piston, can be reduced to a minimum without risking damage
of the pressure sensor by the movements of the pump piston.
- The volume of the pressure channel can be minimized despite placing the pressure sensor
in the middle or even rear region of the pump cylinder.
Brief introduction of the drawings
[0008] The present invention will now be described and explained with the help of the attached
figures and schematic drawings, which present a non-limiting selection of preferred
embodiments of the alternative positive displacement pump arrangement according to
the invention. It is shown in:
- Fig. 1
- a positive displacement pump according to a first embodiment of the present invention,
the main portion of the pressure channel being accomplished as at least one slot in
a piston sleeve that is comprised by the cylinder wall; wherein
Fig. 1A shows the pump piston in its foremost position, and
Fig. 1B shows the pump piston in its rearmost position;
- Fig. 2
- a positive displacement pump according to a second embodiment of the present invention,
the main portion of the pressure channel being accomplished as an extremely short
undercut or a tapper on an outer side of the piston sleeve; wherein
Fig. 2A shows the pump piston in its foremost position, and
Fig. 2B shows the pump piston in its rearmost position;
- Fig. 3
- a positive displacement pump according to a third embodiment of the present invention,
the main portion of the pressure channel being accomplished as an elongated undercut
or a tapper on an outer side of the piston sleeve; wherein
Fig. 3A shows the pump piston in its foremost position, and
Fig. 3B shows the pump piston in its rearmost position;
- Fig. 4
- a positive displacement pump according to a fourth embodiment of the present invention,
the main portion of the pressure channel being accomplished as a combination of a
gorge in the cylinder wall and an undercut or a tapper on an outer side of the piston
sleeve; wherein
Fig. 4A shows the pump piston in its foremost position,
Fig. 4B shows the pump piston in its rearmost position,
Fig. 4C shows a cross section in the level C of Fig. 4A,
Fig. 4D shows a cross section in the level D of Fig. 4B, and
µshows a cross section in the level E of Fig. 4B;
- Fig. 5
- a positive displacement pump according to a fifth embodiment of the present invention,
the main portion of the pressure channel being accomplished as at least one slot in
a piston sleeve extending over the entire length and ending at the open rear end of
the pump cylinder; wherein
Fig. 5A shows the pump piston in a retracted position and a disposable tip attached
to the pump's reception cone,
Fig. 5B shows the pump piston in its foremost position, the disposable tip ejected
from the pump's reception cone, and
Fig. 5C shows a cross section in the level C of Fig. 5B.
Detailed description of the present invention
[0009] In the attached Figures 1-5, preferred embodiments of the positive displacement pump
according to the invention are shown. In each case, the positive displacement pump
1 comprises a pump cylinder 2 with a longitudinal axis 3, a cylinder wall 4 extending
parallel to the longitudinal axis 3, a cylinder bottom 5 extending essentially perpendicular
to the longitudinal axis 3, and a cylinder outlet 6 that is located in or close to
the cylinder bottom 5. The positive displacement pump 1 according to the invention
also comprises a pump piston 7 with a piston front 8 that is reciprocally movable
inside the pump cylinder 2 in direction of the longitudinal axis 3 and a cylinder
space 9 that is located inside the pump cylinder 2 and that is defined by the cylinder
wall 4, the cylinder bottom 5, and the piston front 8. The positive displacement pump
1 according to the invention further comprises a pressure sensor 10 that is located
in or outside of an opening 11 in the cylinder wall 4 or the pump piston 7 for detecting
the pressure in the cylinder space 9 and a pressure channel 12, a main portion 13
thereof extending parallel to the longitudinal axis 3 of the pump cylinder 2, for
providing fluidic connection between the cylinder space 9 and the pressure sensor
10.
[0010] Exemplary embodiments with a cylinder outlet 6 that is located in the cylinder bottom
5 are depicted in the Figs. 1-5. The cylinder outlet 6 can be located in the center
of the cylinder bottom 5 (see Figs.) with the cylinder outlet 6 extending along the
longitudinal axis 3. The cylinder outlet 6 can be located off-center in the cylinder
bottom 5. The cylinder outlet 6 may be located close to the cylinder bottom 5, first
starting essentially perpendicular to the longitudinal axis 3 (as an opening in the
cylinder wall 4) and then ending essentially parallel to the longitudinal axis 3.
[0011] The pressure sensor 10, when located in an opening 11 in the cylinder wall 4, preferably
is positioned such that its pressure transducer front is flush with the inner surface
30 of the cylinder wall 4 (see e.g. Fig 2). The pressure sensor 10, when located outside
of an opening 11 in the cylinder wall 4, preferably is positioned directly to the
outer surface of the cylinder wall 4 (see e.g. Fig. 3). A pressure sensor 10 measures
pressure of fluids, typically of gases, liquids or gas/liquid mixtures. Pressure is
an expression of the force required to stop a fluid from expanding, and is usually
stated in terms of force per unit area.
[0012] A pressure sensor usually acts as a transducer, it generates a signal as a function
of the pressure imposed. For the purposes of this patent application, such a signal
is electrical. The pressure transducer may be selected from a group including a piezoresistive
strain gage and pressure transducers working on the base of capacitive, electromagnetic,
piezoelectric or optical principles. Particularly preferred is a pressure sensor of
the type Honeywell 26PC01SMT (Honeywell Sensing and Control, Golden Valley, MN 55422),
featuring Wheatstone bridge construction, silicon piezoresistive technology, and ratiometric
output.
[0013] In the positive displacement pump 1 according to the invention, the main portion
13 of the pressure channel 12 is located inside of the pump cylinder 2, extending,
at least in a foremost position of the pump piston 7, from the cylinder bottom 5 beyond
or to the opening 11 in the cylinder wall 4 or pump piston 7.
[0014] The main portion 13 of the pressure channel 12, when located inside of the pump cylinder
2, may be accomplished in a variety of embodiments, some of them are depicted in the
Figs. 1-5. In any case, the main portion 13 of the pressure channel 12 extends from
the cylinder bottom 5 beyond or to the opening 11 (in the cylinder wall 4).
[0015] The different embodiments are now described in more detail with the help of the attached
drawings.
[0016] Figure 1 shows a positive displacement pump 1 according to a first embodiment of
the present invention. The main portion 13 of the pressure channel 12 preferably is
accomplished as a single slot 15 in a piston sleeve 14 that is comprised by the cylinder
wall 4. A sealing member 24, preferably in the form of an O-ring or lip seal, is located
between the pump piston 7 and the piston sleeve 14. The sealing member 24 is accomplished
as a moving seal that is captured in a recess 32' of the pump piston 7 and that is
accommodated to slidingly move over the surface of the piston sleeve 14.
[0017] Fig. 1A shows the pump piston 7 in its foremost position, touching with its piston
front 8 the cylinder bottom 5. The opening 11 in the cylinder wall 4 and the sealing
member 24 of the pump piston 7 are positioned such that the pressure sensor 10 is
at the rear border of, but inside the cylinder space 9. The sensor 10 here slightly
protrudes into the main portion 13 of the pressure channel 12 that is provided by
at least one slot 15 in the piston sleeve 14.
[0018] Fig. 1B shows the pump piston 7 in its rearmost position, reaching with its sealing
member 24 almost the rear end 34 of the pump cylinder 2.
[0019] From the embodiment of Fig. 1 it is clear that the opening 11 in the cylinder wall
4 has to be in the lower half of the pump cylinder 2, thus restricting the delivery
volume of the positive displacement pump 1 to about half of the volume of the pump
cylinder 2. The pump cylinder 2 preferably is produced from stainless steel (advantageously
if electrical conductivity for liquid level detection is desired) or from a polymer
material, such as polypropylene. The pump piston 7 and the piston sleeve 14 preferably
are produced from stainless steel. The sealing member 24 preferably is of an inert
rubber such as Neoprene.
[0020] Figure 2 shows a positive displacement pump 1 according to a second embodiment of
the present invention. The main portion 13 of the pressure channel 12 is accomplished
as a tapper 21 on an outer side 22 of the piston sleeve 14. A sealing member 24, preferably
in the form of an O-ring or lip seal, is located between the pump piston 7 and the
piston sleeve 14. The sealing member 24 is accomplished as a moving seal that is captured
in a recess 32' of the pump piston 7 and that is accommodated to slidingly move over
the surface of the piston sleeve 14. The pump piston 7 here comprises a front plate
47 with the piston front 8 and the recess 32' with the sealing member 24. The pump
piston 7 also comprises a piston rod 48 that is engaged by a piston drive. Such a
piston drive (preferably a motor drive 35, see Fig. 5) is preferred for all embodiments
of the present invention in order to equip an automated liquid handling robot or liquid
handling workstation with one or a plurality of positive displacement pumps 1 according
to the invention.
[0021] Fig. 2A shows the pump piston 7 in its foremost position, touching with its piston
front 8 the cylinder bottom 5. The opening 11 in the cylinder wall 4 and thus the
pressure sensor 10 are located close to the cylinder bottom 5. The sealing member
24 of the pump piston 7 is positioned such that it sealingly touches the piston sleeve
14, which leaves open an entrance slit 49 between the lower end of the tapper 21 on
the outer side 22 of the piston sleeve 14 and the cylinder bottom 5. This entrance
slit 49 ensures fluidic connection of the main portion 13 of the pressure channel
12 with the cylinder space 9. The sensor 10 here is flush with the inner surface 30
of the cylinder wall 4.
[0022] Fig. 2B shows the pump piston 7 in its rearmost position, reaching with its sealing
member 24 almost the rear end 34 of the pump cylinder 2.
[0023] From the embodiment of Fig. 2 it is clear that the position of the opening 11 in
the cylinder wall 4 has no influence on the delivery volume of the positive displacement
pump 1. The pump cylinder 2 preferably is produced from stainless steel (advantageously
if electrical conductivity for liquid level detection is desired) or from a polymer
material, such as polypropylene. The pump piston 7 and the piston sleeve 14 preferably
are produced from stainless steel. The sealing member 24 preferably is of an inert
rubber such as Neoprene.
[0024] Figure 3 shows a positive displacement pump 1 according to a third embodiment of
the present invention that is in many respects similar to the second embodiment. The
main portion 13 of the pressure channel 12 is accomplished as an undercut 20 on an
outer side 22 of the piston sleeve 14. A sealing member 24, preferably in the form
of an O-ring or lip seal, is located between the pump piston 7 and the piston sleeve
14. The sealing member 24 is accomplished as a moving seal that is captured in a recess
32' of the pump piston 7 and that is accommodated to slidingly move over the surface
of the piston sleeve 14.
[0025] Fig. 3A shows the pump piston 7 in its foremost position, touching with its piston
front 8 the cylinder bottom 5. The opening 11 in the cylinder wall 4 and thus the
pressure sensor 10 are located about in the middle of the pump cylinder 2. The sealing
member 24 of the pump piston 7 is positioned such that it sealingly touches the piston
sleeve 14, which leaves open an entrance slit 49 between the lower end of the undercut
20 on the outer side 22 of the piston sleeve 14 and the cylinder bottom 5. This entrance
slit 49 ensures fluidic connection of the main portion 13 of the pressure channel
12 with the cylinder space 9. The sensor 10 here is located outside of the cylinder
wall 4. Deviating from Fig. 3, but not from the present invention, the front of the
pressure transducer may at last partially reach into the opening 11 in the cylinder
wall 4 (not shown).
[0026] Fig. 3B shows the pump piston 7 in its rearmost position, reaching with its sealing
member 24 almost the rear end 34 of the pump cylinder 2.
[0027] From the embodiment of Fig. 3 it is clear that the position of the opening 11 in
the cylinder wall 4 has no influence on the delivery volume of the positive displacement
pump 1. Moreover (and distinguishing this third embodiment from the embodiment of
Fig. 2), the location of the opening 11 in the cylinder wall 4 and thus the location
of the pressure sensor 10 can arbitrarily be chosen along almost the whole length
of the pump cylinder 2 and according to the requirements of a liquid handling robot
or liquid handling system (both not shown) the positive displacement pump 1 is attached
to or incorporated in. The pump cylinder 2 preferably is produced from stainless steel
(advantageously if electrical conductivity for liquid level detection is desired)
or from a polymer material, such as polypropylene. The pump piston 7 and the piston
sleeve 14 preferably are produced from stainless steel. The sealing member 24 preferably
is of an inert rubber such as Neoprene.
[0028] The cylinder outlet 6 may be arranged off-center with respect to the longitudinal
axis 3 of the positive displacement pump 1. As noted already, the cylinder outlet
6 then is located close to the cylinder bottom 5, first starting essentially perpendicular
to the longitudinal axis 3 (as an opening in the cylinder wall 4) and then ending
essentially parallel to the longitudinal axis 3. It is well known to linearly arrange
the pipette or dispenser tips 37 of a plurality of similar positive displacement pumps
1 with respect to a Y-axis that runs essentially horizontal and at a right angle with
respect to an X-axis, the latter being the movement direction of a liquid handling
robot along a liquid handling workstation. It also is common to linearly arrange a
plurality of (e.g. eight or twelve) pipette or dispenser tips 37 of similar positive
displacement pumps 1 on the Y-axis in a way that they can be positioned with variable
but equal distance between the individual pipette or dispenser tips 37 of all positive
displacement pumps 1. Thanks to the extreme offset of the cylinder outlets 6 with
respect to the longitudinal axis 3 of each one of the positive displacement pumps
1, the smallest pitch of the pipette or dispenser tips 37 parallel arranged along
a Y-axis can be minimized to only little more than the diameter of the pipette or
dispenser tips 37, if the positive displacement pumps 1 are alternately arranged along
the Y-axis as it is e.g. known from the European patent
EP 1 477 815 B1.
[0029] Figure 4 shows a positive displacement pump 1 according to a fourth embodiment of
the present invention that is in many respects similar to the third embodiment. Also
here, the main portion 13 of the pressure channel 12 is accomplished as an undercut
20 on an outer side 22 of the piston sleeve 14. A sealing member 24, preferably in
the form of an O-ring or lip seal, is located between the pump piston 7 and the piston
sleeve 14. The sealing member 24 is accomplished as a moving seal that is captured
in a recess 32' of the pump piston 7 and that is accommodated to slidingly move over
the surface of the piston sleeve 14. The opening 11 in the cylinder wall 4 and thus
the pressure sensor 10 are located about in the middle of the pump cylinder 2. The
sealing member 24 of the pump piston 7 is positioned such that it sealingly touches
the piston sleeve 14, which leaves open an entrance slit 49 between the lower end
of the undercut 20 on the outer side 22 of the piston sleeve 14 and the cylinder bottom
5. This entrance slit 49 ensures fluidic connection of the main portion 13 of the
pressure channel 12 with the cylinder space 9. The sensor 10 here is located in a
through hole 25 the cylinder wall 4, the sensor being recessed with respect to the
inner surface 30 of the cylinder wall 4. Preferably the pump cylinder 2 is molded
from an inert polymer with left open space that is needed for the accommodation of
the piston sleeve 14 and the gorge 4. The piston sleeve 14 and pump piston 7 preferably
are manufactured from stainless steel. The sealing member 24 preferably is of an inert
rubber such as Neoprene.
[0030] Fig. 4A shows the pump piston 7 in its foremost position, practically touching with
its piston front 8 the cylinder bottom 5.
[0031] Fig. 4B shows the pump piston 7 in its rearmost position, reaching with its sealing
member 24 almost the rear end 34 of the pump cylinder 2.
[0032] From the embodiment of Fig. 4 it is clear that the position of the opening 11 in
the cylinder wall 4 has no influence on the delivery volume of the positive displacement
pump 1. Moreover (and similar to the third embodiment of Fig. 3), the location of
the opening 11 in the cylinder wall 4 and thus the location of the pressure sensor
10 can arbitrarily be chosen along almost the whole length of the pump cylinder 2
and according to the requirements of a liquid handling robot or liquid handling system
(both not shown) the positive displacement pump 1 is attached to or incorporated in.
[0033] Figure 5 shows a positive displacement pump 1 according to a fifth embodiment of
the present invention. The opening 11 in the cylinder wall 4 is accomplished as a
rear opening 26 at an end 34 of the pump cylinder 2 that is opposite to the cylinder
bottom 5. The main portion 13 of the pressure channel 12 is accomplished as at least
one slot 15 in a piston sleeve 14 that is comprised by the cylinder wall 4. The piston
sleeve 14 extends over essentially the entire length of the pump cylinder 2 and the
at least one slot 15 in the piston sleeve 14 extends over essentially the entire length
of the piston sleeve 14. The pressure sensor 10 is located outside the opening 11
(the rear opening 26 in this case) of the cylinder wall 4 and a transverse channel
31 fluidly connects the pressure sensor 10 with the pressure channel 12. A sealing
member 24, preferably in the form of an O-ring or lip seal, is accomplished as a stationary
seal that is captured in a recess 32 of a cylindrical part 33 located at the rear
end 34 of the pump cylinder 2. The sealing member 24 is accommodated to be slidingly
and sealingly contacted by the surface of the moving piston sleeve 14. A motor drive
35 preferably is located close to the pump piston 7 for reciprocally driving the pump
piston 7 in direction of the longitudinal axis 3. A reception cone 36 for receiving
a disposable pipette or dispenser tip 37 is located at and coaxial with the cylinder
outlet. The positive displacement pump 1 according to the eighth embodiment in addition
comprises an ejection tube 38 for ejecting a disposable pipette or dispenser tip 37
from the reception cone 36. This ejection tube 38 is coaxially arranged with and positioned
on the outer side of the pump cylinder 2. At or close to its top, the ejection tube
38 comprises an outwards protruding flange 39 for abutment with an ejection actuator
40. At its base, the ejection tube 38 comprises an inwards protruding flange 39 for
abutment with the rear rim of a disposable pipette or dispenser tip 37. At all necessary
places, O-rings 42 are preferred to seal the pump cylinder 2 against the environment.
A casing 51 preferably encloses the sensor 10 and is sealingly pressed against the
cylindrical, part 33 using a forcing screw 46 (exemplified in the Fig. 5 as a black
triangle).
[0034] Fig. 5A shows the pump piston 7 in a retracted position and a disposable tip 37 attached
to the pump's reception cone 36. The motor drive 35 in a first version is equipped
with a gear wheel 44 driving the pump piston 7 which is equipped on its rear side
28 with a gear rack 43. However, any other appropriate drive could be used for reciprocally
moving the pump piston 7 in the pump cylinder 2. Preferably another or the same motorized
drive is used for actuating the ejection actuator 40, which preferably is equipped
with a retaining spring (not shown). For guiding the pump piston 7 inside of the pump
cylinder 2, a guide bushing 52 may be provided. This guide bushing 52 preferably is
applied around the pump piston 7 and close to the piston front 8. Here, the guide
bushing 52 (that travels with the piston) cannot touch or otherwise compromise the
sensor 10 when moving past the position of the sensor 10, because of the at least
one slot 15 in the piston sleeve 14. In consequence, this guide bushing 52 does not
need a hole or cutout 53. For minimizing dead volume, and thus increasing accuracy
of the positive displacement pump 1, a single slot 15 is preferred.
[0035] Fig. 5B shows the pump piston 7 in its foremost position, practically touching with
its piston front 8 the cylinder bottom 5. Deviating from the Figs. 1-4, the piston
front 8 in this embodiment is not plane but formed as a flat cone. Deviating from
all presented embodiments, the piston front 8 may show a dome shape (not shown). The
ejection tube 38 is pushed by the ejection actuator 40 to its lowermost position by
which a previously mounted disposable pipette or dispenser tip 37 has been ejected.
The motor drive 35 in a second version is equipped with a threaded rod 45 and a movement
transmitter 41 for driving the pump piston 7 by attachment to its rear side 28. Preferably,
the ejection actuator 40 is accomplished to be actuated by the motor drive 35 for
reciprocally driving the pump piston 7 in direction of the longitudinal axis 3 via
a movement transmitter 41 to eject the disposable pipette or dispenser tip 37 from
the reception cone 36 simultaneously with a very last increment of a dispensed sample
volume. In order to assist tip ejection and to amplify the movement of the ejection
actuator 40, a rocker arm lever 50 is placed in working connection between the movement
transmitter 41 and the ejection actuator 40. However, any other appropriate drive
could be used for reciprocally moving the pump piston 7 in the pump cylinder 2. Preferably
another or the same motorized drive is used for actuating the ejection actuator 40,
which preferably is equipped with a retaining spring (not shown).
[0036] From the embodiment of Fig. 5 it is clear that the position of the sealing member
24 is such that it seals the pump cylinder 2 at a level that is more distal with respect
to the cylinder bottom 5 than the rear end 34 of the pump cylinder 2; this position
is enabled by the cylindrical part 33. Especially according to the second variant,
in which no gear rack 43 is necessary for driving the pump piston 7, the maximum delivery
volume of the positive displacement pump 1 is about equal to the volume of the pump
cylinder 2. The pump cylinder 2 preferably is produced from stainless steel (advantageously
if electrical conductivity for liquid level detection is desired) or from a polymer
material, such as polypropylene. The pump piston 7 preferably is produced from stainless
steel and the piston sleeve 14 preferably is produced from Teflon
® (DuPont, Wilmington, USA). The sealing member 24 preferably is of an inert rubber
such as Neoprene.
[0037] In general, the piston sleeve 14 is regarded as a part of the cylinder wall 4, even
when it is accomplished as an insert that is pushed into the pump cylinder 2 from
its rear end 34 during assembling of the positive displacement pump 1. Preferably,
the positive displacement pump 1 is used for compressing and/or expanding a gas that
advantageously is not miscible with a sample liquid (air or nitrogen gas). The gas
in turn is used to push out (dispense) or aspirate a liquid sample volume that is
preferably not larger than the volume of the utilized pipette or dispenser tip 37.
Thus, the positive displacement pump 1 most preferably is accomplished and utilized
as an air displacement pump.
[0038] In addition to the seal member 24 in the form of e.g. O-rings, lip seals, or combinations
thereof, the provision of a liquid seal or gland fluid seal (e.g. from IVEK CORP.
North Springfield, Vermont 05150, USA) is envisaged too. If such a liquid seal is
chosen (alone or in combination with any one of the above seal members 24) between
the pump piston 7 and the cylinder wall 4 for sealing the cylinder against the environment;
the positive displacement pump 1 preferably is accomplished and utilized as a liquid
displacement pump.
[0039] The same reference numerals refer to the same features, even when not in all cases
the reference numeral is indicated in a drawing or individually addressed in the specification.
Reference numerals:
[0040]
- 1
- positive displacement pump
- 2
- pump cylinder
- 3
- longitudinal axis
- 4
- cylinder wall
- 5
- cylinder bottom
- 6
- cylinder outlet
- 7
- pump piston
- 8
- piston front
- 9
- cylinder space
- 10
- pressure sensor
- 11
- opening in 4
- 12
- pressure channel
- 13
- main portion of 12
- 14
- piston sleeve
- 15
- slot(s) in 14
- 20
- undercut on an outer side of 14
- 21
- tapper on an outer side of 14
- 22
- outer side of 14
- 23
- gorge in 4
- 24
- sealing member
- 25
- through hole
- 26
- rear opening
- 27
- rear end of 7
- 28
- rear side of 7
- 30
- inner surface of 4
- 31
- transverse channel
- 32,32'
- recess
- 33
- cylindrical part
- 34
- rear end of 2
- 35
- motor drive
- 36
- reception cone
- 37
- disposable pipette or dispenser tip
- 38
- ejection tube
- 39
- flange
- 40
- ejection actuator
- 41
- movement transmitter
- 42
- O-ring
- 43
- gear rack
- 44
- gear wheel
- 45
- threaded rod
- 46
- forcing screw
- 47
- front plate
- 48
- piston rod
- 49
- entrance slit
- 50
- rocker arm lever
- 51
- casing
- 52
- guide bushing
- 53
- hole, cutout in 52
1. A positive displacement pump (1) comprising:
- a pump cylinder (2) with a longitudinal axis (3), a cylinder wall (4) extending
parallel to the longitudinal axis (3), a cylinder bottom (5) extending essentially
perpendicular to the longitudinal axis (3), and a cylinder outlet (6) that is located
in or close to the cylinder bottom (5);
- a pump piston (7) with a piston front (8) that is reciprocally movable inside the
pump cylinder (2) in a direction of the longitudinal axis (3);
- a cylinder space (9) that is located inside the pump cylinder (2) and that is defined
by the cylinder wall (4), the cylinder bottom (5), and the piston front (8);
- a pressure sensor (10) that is located in or outside of an opening (11) in the cylinder
wall (4) for detecting the pressure in the cylinder space (9); and
- a pressure channel (12), a main portion (13) thereof extending parallel to the longitudinal
axis (3) of the pump cylinder (2), for providing fluidic connection between the cylinder
space (9) and the pressure sensor (10),
characterized in that the cylinder wall (4) comprises a piston sleeve (14), the piston sleeve (14) being
located on the inner side of the cylinder wall (4) and extending over essentially
the entire length of the pump cylinder (2) to the cylinder bottom (5),
and
in that the main portion (13) of the pressure channel (12) is located in the cylinder wall
(4) comprising the piston sleeve (14), the piston sleeve (14) thus preventing the
pump piston (7) from touching or compromising the pressure sensor (10) or an inner
surface (30) of the cylinder wall (4) when moving past the position of the pressure
sensor (10).
2. The positive displacement pump (1) of claim 1, characterized in that the opening (11) in the cylinder wall (4) is accomplished as a through hole (25)
in the cylinder wall (4) or as a rear opening (26) at an end (34) of the pump cylinder
(2) that is opposite to the cylinder bottom (5).
3. The positive displacement pump (1) of claim 1 or 2, characterized in that the main portion (13) of the pressure channel (12) is accomplished as at least one
slot (15) in the piston sleeve (14).
4. The positive displacement pump (1) of claim 3, characterized in that the at least one slot (15) in the piston sleeve (14) extends over essentially the
entire length of the piston sleeve (14).
5. The positive displacement pump (1) of one of the preceding claims, characterized in that the main portion (13) of the pressure channel (12) is accomplished as an undercut
(20) or a tapper (21) on an outer side (22) of the piston sleeve (14).
6. The positive displacement pump (1) of claim 1, characterized in that the main portion (13) of the pressure channel (12) is accomplished as a gorge (23)
in the cylinder wall (4).
7. The positive displacement pump (1) of one of the preceding claims, characterized in that the pump piston (7) comprises at least one guide bushing (52) that is applied around
and that travels with the pump piston (7)
8. The positive displacement pump (1) of one of the claims 1 to 7, characterized in that the pressure sensor (10) is located in the opening (11) and Flush or recessed with
respect to the inner surface (30) of the cylinder wall (4).
9. The positive displacement pump (1) of one of the claims 1 to 7, characterized in that the pressure sensor (10) is located outside the opening (11) of the cylinder wall
(4), a transverse channel (31) fluidly connecting the pressure sensor (10) with the
pressure channel (12).
10. The positive displacement pump (1) of one of the preceding claims, characterized in that a sealing member (24) is located between the pump piston (7) and the cylinder wall
(4) or the piston sleeve (14).
11. The positive displacement pump (1) of claim 10, characterized in that the sealing member (24) is accomplished as a stationary seal that is captured in
a recess (32) of the cylinder wall (4), of the piston sleeve (14), or of a cylindrical
part (33) located at a rear end (34) of the pump cylinder (2).
12. The positive displacement pump (1) of claim 10, characterized in that the sealing member (24) is accomplished as a moving seal that is captured in a recess
(32') of the pump piston (7).
13. The positive displacement pump (1) of one of the preceding claims, characterized in that the positive displacement pump (1) comprises a motor drive (35) for reciprocally
driving the pump piston (7) in the direction of the longitudinal axis (3).
14. The positive displacement pump (1) of one of the preceding claims, characterized in that the positive displacement pump (1) comprises a reception cone (36) for receiving
a disposable pipette or dispenser tip (37).
15. The positive displacement pump (1) of claim 14, characterized in that the positive displacement pump (1) comprises an ejection tube (38) for ejecting a
disposable pipette or dispenser tip (37) from the reception cone (36).
16. The positive displacement pump (1) of claim 15, characterized in that the ejection tube (38) comprises a flange (39) for abutment with an ejection actuator
(40).
17. The positive displacement pump (1) of claim 16, characterized in that the ejection actuator (40) is accomplished to be actuated by the motor drive (35)
for reciprocally driving the pump piston (7) in the direction of the longitudinal
axis (3) via a movement transmitter (41) to eject the disposable pipette or dispenser
tip (37) from the reception cone (36) simultaneously with a very last increment of
a dispensed sample volume.
18. A liquid handling robot that is accomplished to take up and/or deposit liquid samples,
characterized in that the liquid handling robot comprises a single or multiple arrangement of the positive
displacement pump (1) of one of the preceding claims.
19. A liquid handling workstation that comprises a liquid handling robot with a multiple
arrangement of the positive displacement pump (1) according to claim 18, characterized in that the multiple arrangement of the positive displacement pump (1) is accomplished to
receive a plurality of pipette or dispenser tips (37), which are arranged on a Y-axis
that runs essentially horizontal and at a right angle with respect to an X-axis, the
X-axis being the movement direction of the liquid handling robot along the liquid
handling workstation.
1. Verdrängerpumpe (1), umfassend:
- einen Pumpenzylinder (2) mit einer Längsachse (3), einer Zylinderwand (4), die sich
parallel zur Längsachse (3) erstreckt, einem Zylinderboden (5), der sich im Wesentlichen
senkrecht zur Längsachse (3) erstreckt, und einem Zylinderauslass (6), der in oder
nahe dem Zylinderboden (5) angeordnet ist;
- einen Pumpenkolben (7) mit einer Kolbenfront (8), die in dem Pumpenzylinder (2)
in einer Richtung der Längsachse (3) hin- und hergehend beweglich ist;
- einen Zylinderraum (9), der im Pumpenzylinder (2) angeordnet ist und durch die Zylinderwand
(4), den Zylinderboden (5) und die Kolbenfront (8) definiert wird;
- einen Drucksensor (10), der innerhalb oder ausserhalb einer Öffnung (11) in der
Zylinderwand (4) angeordnet ist, um den Druck im Zylinderraum (9) zu erfassen; und
- einen Druckkanal (12), wobei sich ein Hauptteil (13) davon parallel zur Längsachse
(3) des Pumpenzylinders (2) erstreckt, um eine Fluidverbindung zwischen dem Zylinderraum
(9) und dem Drucksensor (10) bereitzustellen,
dadurch gekennzeichnet, dass die Zylinderwand (4) eine Kolbenbuchse (14) umfasst, wobei die Kolbenbuchse (14)
an der Innenseite der Zylinderwand (4) angeordnet ist und sich im Wesentlichen über
die gesamte Länge des Pumpenzylinders (2) zum Zylinderboden (5) erstreckt,
und dass der Hauptteil (13) des Druckkanals (12) in der Zylinderwand (4) angeordnet
ist, welche die Kolbenbuchse (14) umfasst, wodurch die Kolbenbuchse (14) den Pumpenkolben
(7) daran hindert, den Drucksensor (10) oder eine Innenfläche (30) der Zylinderwand
(4) zu berühren oder zu beschädigen, wenn er sich an der Position des Drucksensors
(10) vorbeibewegt.
2. Verdrängerpumpe (1) nach Anspruch 1, dadurch gekennzeichnet, dass die Öffnung (11) in der Zylinderwand (4) als Durchgangsloch (25) in der Zylinderwand
(4) oder als hintere Öffnung (26) an einem Ende (34) des Pumpenzylinders (2), das
dem Zylinderboden (5) entgegengesetzt ist, ausgeführt ist.
3. Verdrängerpumpe (1) nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der Hauptteil (13) des Druckkanals (12) als wenigstens ein Schlitz (15) in der Kolbenbuchse
(14) ausgeführt ist.
4. Verdrängerpumpe (1) nach Anspruch 3, dadurch gekennzeichnet, dass sich der wenigstens eine Schlitz (15) in der Kolbenbuchse (14) über im Wesentlichen
die gesamte Länge der Kolbenbuchse (14) erstreckt.
5. Verdrängerpumpe (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass der Hauptteil (13) des Druckkanals (12) als Hinterschneidung (20) oder Abschrägung
(21) an einer Aussenseite (22) der Kolbenbuchse (14) ausgeführt ist.
6. Verdrängerpumpe (1) nach Anspruch 1, dadurch gekennzeichnet, dass der Hauptteil (13) des Druckkanals (12) als Hohlkehle (23) in der Zylinderwand (4)
ausgeführt ist.
7. Verdrängerpumpe (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass der Pumpenkolben (7) wenigstens eine Führungsbuchse (52) umfasst, die um den Pumpenkolben
(7) herum angebracht ist und sich mit ihm bewegt.
8. Verdrängerpumpe (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass der Drucksensor (10) in der Öffnung (11) angeordnet ist und in Bezug auf die Innenfläche
(30) der Zylinderwand (4) bündig ist oder zurückspringt.
9. Verdrängerpumpe (1) nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass der Drucksensor (10) ausserhalb der Öffnung (11) der Zylinderwand (4) angeordnet
ist, wobei ein Querkanal (31) den Drucksensor (10) fluidmässig mit dem Druckkanal
(12) verbindet.
10. Verdrängerpumpe (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass ein Dichtelement (24) zwischen dem Pumpenkolben (7) und der Zylinderwand (4) oder
der Kolbenbuchse (14) angeordnet ist.
11. Verdrängerpumpe (1) nach Anspruch 10, dadurch gekennzeichnet, dass das Dichtelement (24) als stationäre Dichtung ausgeführt ist, die in einer Ausnehmung
(32) der Zylinderwand (4), der Kolbenbuchse (14) oder eines zylindrischen Teils (33)
untergebracht ist, der an einem hinteren Ende (34) des Pumpenzylinders (2) angeordnet
ist.
12. Verdrängerpumpe (1) nach Anspruch 10, dadurch gekennzeichnet, dass das Dichtelement (24) als bewegliche Dichtung ausgeführt ist, die in einer Ausnehmung
(32') des Pumpenkolbens (7) untergebracht ist.
13. Verdrängerpumpe (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Verdrängerpumpe (1) einen Motorantrieb (35) umfasst, um den Pumpenkolben (7)
in eine hin- und hergehende Bewegung in der Richtung der Längsachse (3) zu versetzen.
14. Verdrängerpumpe (1) nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Verdrängerpumpe (1) einen Aufnahmekonus (36) zur Aufnahme einer Einwegpipetten-
oder Abgabe-Spitze (37) umfasst.
15. Verdrängerpumpe (1) nach Anspruch 14, dadurch gekennzeichnet, dass die Verdrängerpumpe (1) ein Abwurfrohr (38) umfasst, um eine Einwegpipetten- oder
Abgabe-Spitze (37) von dem Aufnahmekonus (36) zu stossen.
16. Verdrängerpumpe (1) nach Anspruch 15, dadurch gekennzeichnet, dass das Abwurfrohr (38) einen Flansch (39) umfasst, der mit einem Abwurfaktuator (40)
beaufschlagbar ist.
17. Verdrängerpumpe (1) nach Anspruch 16, dadurch gekennzeichnet, dass der Abwurfaktuator (40) dafür ausgelegt ist, durch den Motorantrieb (35) betätigt
zu werden, der den Pumpenkolben (7) in eine hin- und hergehende Bewegung in der Richtung
der Längsachse (3) versetzt, um über eine Bewegungsübertragungsvorrichtung (41) die
Einwegpipetten- oder Abgabe-Spitze (37) gleichzeitig mit dem allerletzten Teil eines
abgegebenen Probenvolumens von dem Aufnahmekonus (36) abzuwerfen.
18. Liquidhandling-Roboter, der dafür ausgelegt ist, flüssige Proben aufzunehmen und/oder
abzugeben, dadurch gekennzeichnet, dass der Flüssigkeitshandhabungsroboter eine Einzel- oder Mehrfachanordnung der Verdrängerpumpe
(1) nach einem der vorhergehenden Ansprüche umfasst.
19. Liquidhandling-Arbeitsstation, die einen Liquidhandling-Roboter mit einer Mehrfachanordnung
der Verdrängerpumpe (1) nach Anspruch 18 umfasst, dadurch gekennzeichnet, dass die Mehrfachanordnung der Verdrängerpumpe (1) dafür ausgelegt ist, eine Vielzahl
von Pipetten- oder Abgabe-Spitzen (37) aufzunehmen, die auf einer Y-Achse angeordnet
sind, die im Wesentlichen horizontal und im rechten Winkel in Bezug auf eine X-Achse
verläuft, wobei die X-Achse die Bewegungsrichtung des Liquidhandling-Roboters entlang
der Liquidhandling-Arbeitsstation ist.
1. Pompe volumétrique (1) comprenant :
- un cylindre de pompe (2) avec un axe longitudinal (3), une paroi de cylindre (4)
s'étendant parallèlement à l'axe longitudinal (3), un fond de cylindre (5) s'étendant
de façon essentiellement perpendiculaire à l'axe longitudinal (3), et une sortie de
cylindre (6) qui est placée dans le fond de cylindre (5) ou près de celui-ci ;
- un piston de pompe (7) avec une partie avant de piston (8) qui est mobile selon
un mouvement de va-et-vient à l'intérieur du cylindre de pompe (2) dans une direction
de l'axe longitudinal (3) ;
- une chambre de cylindre (9) qui est située à l'intérieur du cylindre de pompe (2)
et qui est définie par la paroi de cylindre (4), le fond de cylindre (5) et la partie
avant de piston (8) ;
- un capteur de pression (10) qui est situé à l'intérieur ou à l'extérieur d'une ouverture
(11) dans la paroi de cylindre (4) pour détecter la pression dans la chambre de cylindre
(9) ; et
- un canal de pression (12), dont une partie principale (13) s'étend parallèlement
à l'axe longitudinal (3) du cylindre de pompe (2), pour assurer une liaison fluidique
entre la chambre de cylindre (9) et le capteur de pression (10),
caractérisée en ce que la paroi de cylindre (4) comprend un manchon de piston (14), le manchon de piston
(14) étant situé sur le côté intérieur de la paroi de cylindre (4) et s'étendant sur
essentiellement toute la longueur du cylindre de pompe (2) jusqu'au fond de cylindre
(5),
et
en ce que la partie principale (13) du canal de pression (12) est située dans la paroi de cylindre
(4) comprenant le manchon de piston (14), le manchon de piston (14) empêchant ainsi
le piston de pompe (7) de toucher ou gêner le capteur de pression (10) ou une surface
intérieure (30) de la paroi de cylindre (4) quand il se déplace au-delà de la position
du capteur de pression (10).
2. Pompe volumétrique (1) selon la revendication 1, caractérisée en ce que l'ouverture (11) dans la paroi de cylindre (4) est réalisée sous la forme d'un trou
traversant (25) dans la paroi de cylindre (4) ou sous la forme d'une ouverture arrière
(26) à une extrémité (34) du cylindre de pompe (2) qui est opposée au fond de cylindre
(5).
3. Pompe volumétrique (1) selon la revendication 1 ou 2, caractérisée en ce que la partie principale (13) du canal de pression (12) est réalisée sous la forme d'au
moins une fente (15) dans le manchon de piston (14).
4. Pompe volumétrique (1) selon la revendication 3, caractérisée en ce que ladite au moins une fente (15) dans le manchon de piston (14) s'étend sur essentiellement
toute la longueur du manchon de piston (14).
5. Pompe volumétrique (1) selon l'une des revendications précédentes, caractérisée en ce que la partie principale (13) du canal de pression (12) est réalisée sous la forme d'un
surplomb (20) ou d'une partie effilée (21) sur un côté extérieur (22) du manchon de
piston (14).
6. Pompe volumétrique (1) selon la revendication 1, caractérisée en ce que la partie principale (13) du canal de pression (12) est réalisée sous la forme d'une
gorge (23) dans la paroi de cylindre (4).
7. Pompe volumétrique (1) selon l'une des revendications précédentes, caractérisée en ce que le piston de pompe (7) comprend au moins une bague de guidage (52) qui est appliquée
autour du piston de pompe (7) et qui se déplace avec celui-ci.
8. Pompe volumétrique (1) selon l'une des revendications précédentes, caractérisée en ce que le capteur de pression (10) est situé dans l'ouverture (11) et à fleur ou renfoncé
par rapport à la surface intérieure (30) de la paroi de cylindre (4).
9. Pompe volumétrique (1) selon l'une des revendications 1 à 7, caractérisée en ce que le capteur de pression (10) est situé à l'extérieur de l'ouverture (11) de la paroi
de cylindre (4), un canal transversal (31) assurant la liaison fluidique entre le
capteur de pression (10) et le canal de pression (12).
10. Pompe volumétrique (1) selon l'une des revendications précédentes, caractérisée en ce qu'un élément d'étanchéité (24) est situé entre le piston de pompe (7) et la paroi de
cylindre (4) ou le manchon de piston (14).
11. Pompe volumétrique (1) selon la revendication 10, caractérisée en ce que l'élément d'étanchéité (24) est réalisé sous la forme d'un joint fixe qui est retenu
dans un évidement (32) de la paroi de cylindre (4), du manchon de piston (14), ou
d'une partie cylindrique (33) située à une extrémité arrière (34) du cylindre de pompe
(2).
12. Pompe volumétrique (1) selon la revendication 10, caractérisée en ce que l'élément d'étanchéité (24) est réalisé sous la forme d'un joint mobile qui est retenu
dans un évidement (32') du piston de pompe (7).
13. Pompe volumétrique (1) selon l'une des revendications précédentes, caractérisée en ce que la pompe volumétrique (1) comprend un entraînement à moteur (35) pour entraîner dans
un mouvement de va-et-vient le piston de pompe (7) dans la direction de l'axe longitudinal
(3).
14. Pompe volumétrique (1) selon l'une des revendications précédentes, caractérisée en ce que la pompe volumétrique (1) comprend un cône de réception (36) pour recevoir un embout
jetable de pipette ou de distributeur (37).
15. Pompe volumétrique (1) selon la revendication 14, caractérisée en ce que la pompe volumétrique (1) comprend un tube d'éjection (38) pour éjecter un embout
jetable de pipette ou de distributeur (37) du cône de réception (36).
16. Pompe volumétrique (1) selon la revendication 15, caractérisée en ce que le tube d'éjection (38) comprend un rebord (39) pour venir en butée sur un actionneur
d'éjection (40).
17. Pompe volumétrique (1) selon la revendication 16, caractérisée en ce que l'actionneur d'éjection (40) est réalisé de manière à être actionné par l'entraînement
à moteur (35), pour entraîner dans un mouvement de va-et-vient le piston de pompe
(7) dans la direction de l'axe longitudinal (3), via un transmetteur de mouvement
(41) pour éjecter l'embout jetable de pipette ou de distributeur (37) du cône de réception
(36) simultanément à un tout dernier incrément d'un volume d'échantillon distribué.
18. Robot de manipulation de liquides réalisé pour prélever et/ou déposer des échantillons
de liquides, caractérisé en ce que le robot de manipulation de liquides comprend un agencement unique ou multiple de
pompe volumétrique (1) selon l'une des revendications précédentes.
19. Poste de manipulation de liquides qui comprend un robot de manipulation de liquides
avec un agencement multiple de pompe volumétrique (1) selon la revendication 18, caractérisé en ce que l'agencement multiple de pompe volumétrique (1) est réalisé pour recevoir une pluralité
d'embouts de pipette ou de distributeur (37), qui sont agencés sur un axe Y qui s'étend
de façon essentiellement horizontale et à angle droit par rapport à un axe X, l'axe
X correspondant à la direction de mouvement du robot de manipulation de liquides le
long du poste de manipulation de liquides.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description